Holding devices of this kind are used, for example, as separators in production or assembly lines. The transport unit in this instance can be comprised of a work piece holder, a work piece, or the like.
EP 0 036 955 A2 has disclosed a species-defining holding device in which the individual components, in particular the actuator embodied in the form of a pneumatically operating cylinder/piston unit and the two sensor units respectively provided for detecting the presence of a transport unit before or after the actuator, are attached to one another to form a combined unit. In addition, a control unit is provided, which receives the detection results of the sensor units and derives actuation signals for triggering the actuator based on these signals. A particular disadvantage of the known holding device is that the individual components are relatively unprotected from external influences.